First of all I believe the M6GC will not have more power.
There is no reason for BMW to make the car any different than M5.
They pretty much serve the same purpose.

I'll say The one M car to look forward to is the "M1/M10" (which BMW just patented)

Not long ago there was one M car above 4200 lbs, the M6 vert. With this M6GC there will be no less than 6 and only two below whereof one is a vert. Is that a good evolvement of M cars? You can't help but guessing that the aim has shifted from building bad @ss enthusiasts cars to "follow the money" to some extent.